Browsers

My recommendations:

macOS/iOS: Safari
other: Chrome

Versions of all "major" browsers:

browser β developer nightly platforms
Safari* Technology Preview macOS/iOS*, Linux (T.P. on macOS & Linux only)
Chrome* β Dev Canary macOS/iOS*, Windows, Linux/Android
Opera* β Developer macOS/iOS*, Windows, Linux/Android
Firefox β Developer Nightly macOS/iOS*, Windows, Linux/Android
Edge*‡ β Dev Canary macOS/iOS*, Windows, Linux (soon)/Android
 
‡ Replaced Internet Explorer:
Windows XPVista7,...
runs IE 89Edge
*  originally developed the HTML renderer Webkit (based on KHTML) for Safari as open source.
  • The proxy browser UC Browser uses U3, based on Webkit.
  • Webkit on Linux is known as "Epiphany".
  • iOS browsers are restricted by  to use Webkit.
Chrome uses Blink (Chromium), based by Google on Webkit.
  • Opera, Samsung Internet, & Edge also use Blink.

Mailers

My recommendations:

macOS/iOS: Mail
browser elsewhere: iCloud
browser w/o iCloud account: Gmail

(Don't even think about using one named after a tree.)